N for Wheat: Timing is Everything

This winter keeps dragging on and its is hard not to get anxious about the upcoming crop year. Climateologists are predicting a generally normal to cool spring with normal precipitation, but soil temperatures are still very low. Wheat growers in particular are thinking about getting their crop off to a good start, but applying nitrogen too early can often add up to nitrogen loss and money wasted.

According to a recent post in the Ohio C.O.R.N. newsletter, research has shown yield losses from relying on nitrogen applied before green-up no mater what the N source. Nitrogen applications on wheat, in fact, do very little good until the plant reaches sufficient maturity to utilize the nutrient, between green-up and into early elongation. Research done at the Ohio State University has shown that early N applications may do very little good for yield potential, and that enough soil organic N exists to get wheat going in most Ohio soils.

However, waiting too long can have equally limiting effects on yield potential and applications made at early boot come too late.

Researchers Ed Lentz and Laura Lindsey note, "... a practical compromise is to topdress N any time fields are suitable for application after initial green-up to early stem elongation. There is still a potential for loss even at green-up applications. To lessen this risk a producer may want to use a N source that has the least potential for loss for earlier applications. The source of N is not as critical as the application date approaches stem elongation."

So with a cool spring ahead and a tough winter nearly behind us, early crop development may be slow this spring. Applying nitrogen to wheat is as much about timing as anything. In order to maximize your nitrogen dollars, time nitrogen applications after green-up and before boot stage during the elongation stage. This will provide vital nitrogen to the crop when it is most prepared to utilize it. In that way, yield potential can be realized with minimal risk of N loss.